The present invention relates generally to security tags used with electronic security systems for detecting the unauthorized removal of articles and, more particularly, to such security tags which are particularly adapted for use with a compact disc container.
The use of electronic article security systems for detecting and preventing theft or other unauthorized removal of articles or goods from retail establishments and/or other facilities, such as libraries, has become widespread. In general, such security systems employ a security tag which is associated with or is secured to an article (or its packaging) which is readily accessible to potential customers or facility users and, therefore, may be easily removed. Security tags may take on many different sizes, shapes and forms, depending upon the, particular type of security system in use, the type and size of the article, its packaging, etc. In general, such electronic security systems are employed for detecting the presence (or the absence) of a security tag and, thus, a protected article, as the protected article passes through or near a surveilled security area. In most cases, the surveilled area is located at or around an exit or entrance to the retail establishment or other facility.
One such electronic article security system which has gained widespread popularity utilizes a security tag which includes a self-contained, operatively tuned or resonant circuit in the form of a small, generally planar printed circuit which resonates at a predetermined detection frequency within a predetermined detection frequency range. A transmitter, which is also tuned to the detection frequency, is employed for transmitting electromagnetic energy into the surveilled area. A receiver, also tuned to the detection frequency, is positioned generally proximate to the surveilled area. Typically, the transmitter is located on one side of an exit and the receiver is located on the other side of the exit so that a person must pass between the transmitter and the receiver in order to exit the facility. In this manner, when an article having an attached security tag moves into or otherwise passes through the surveilled area, the tag is exposed to the transmitted energy. Upon receiving the transmitted energy, the resonant circuit of the tag resonates, providing an output signal detectable by the receiver. When the receiver detects such an output signal, indicative of the presence of an article with a security tag within the surveilled area, the receiver activates an alarm to alert appropriate security or other personnel.
Electronic article security systems of the type discussed above have been shown to be very effective in preventing the theft or unauthorized removal of articles, particularly articles which are relatively high in value and relatively small in size, such as jewelry, expensive clothing, video cassettes, etc. Small sized, relatively expensive items which are not protected by such systems are relatively easy prey because it is a relatively simple matter for a thief to insert articles of this type into a pocket, pocketbook or under an article of clothing and there is little likelihood that the theft of such articles could be detected by visual inspection.
One such small, but relatively expensive, article which has become increasingly vulnerable to theft due to its rise in popularity is the compact disc. Compact discs are typically stocked and sold in a generally flat, rectangularly shaped plastic container having a width which generally corresponds to the diameter of the compact disc (approximately 43/4 inches) and a length which is slightly greater than the diameter of the compact disc (about 51/2 inches). The container includes an insert having an annular groove approximately the same size as the compact disc for receiving and holding the compact disc. The relatively hard plastic container, in combination with the insert, provides protection for the compact disc during shipment and storage, affords an attractive display for the compact disc and provides further protection and convenient storage for the compact disc after it has been sold. Thus, because of the size and shape of the compact disc container, it is a relatively easy task for a thief to remove one or more compacts discs, each within its own container, with little concern that the theft of the compact disc will be visually detected.
The present invention relates to a security tag which is particularly adapted for use with a compact disc container holding a compact disc. A security tag made in accordance with the present invention is sized and shaped to fit within the compact disc container at a relatively unnoticeable position between the container insert and the bottom of the compact disc container. The security tag of the present invention makes use of the properties of the compact disc in defining the resonant frequency of the tag. The security tag of the present invention is also specifically designed to prevent the metal within the compact disc from blocking or otherwise interfering with the ability of the tag to resonate when located within a surveilled security area of an electronic article security system of the type described above.